In Tenchu: Wrath of Heaven each of the 3 playable characters has unlockable special moves. Ayame and Rikimaru have 10 special moves. Tesshu has 6 special moves. Ayame and Rikimaru can unlock one special move per mission upon filling their Kuji-meters. You can only unlock one particular move per mission, with the exception of the missions “Assassinate the Evil Tenrai – A and B”. You can learn the same move in those 2 missions.
Tesshu’s special moves are all unlocked from the beginning on. Once a new ability has been learned you can’t lose it anymore and use it throughout the whole game (all missions story mode and multiplayer mode).

When you play a mission with Ayame or Rikimaru you see 9 blue kanji on the bottom left of your screen, this is your Kuji-meter. It consists of 9 kanji read from left to right as : RIN, PYO, TOH, SHA, KAI, JIN, RETSU, ZAI, ZEN. The Kuji-Kiri is basically a spell casted to strengthen your spirit and to protect you from evil forces. Once you have lit all 9 kanji you will see a little animation where Ayame and Rikimaru cast the Kuji-Kiri spell.
Listen to Rikimaru casting the Kuji-Kiri.

There are several ways to light the 9 kanji all involve you killing unsuspecting enemies. Each kanji itself can be divided into 4 parts. Depending on what methods you choose to stealthily kill an enemy you will light between 1/4 and 1 and a half kanji. Every time you have successfully lit a whole kanji, the screen will freeze for a second showing you the kanji you just lit. The only way to loose all your lit kanji is by killing an innocent!

Stealth Kills
Ayame and Rikimaru have 6 stealth kills. Stealth killing a guard will light 1 kanji, unless you stealth kill an enemy while standing in front of him or approaching him from in front, then 1 and a half kanji will be lit.
Notice if you are too far away from your victim when activating the stealth kill you will only light a half kanji! No stealth kill animation is shown in this case.
Using the spear will count as an item kill and only light a half kanji, you will still get added 20 points to your score for successful stealth kill though.

Item Kills
Of course you can use all items that deal damage to stealthily kill your opponents.
Using the Blow Gun to stealth kill an opponent will only reward you with a 1/4 lit kanji.
All other items will reward you with 1/2 lit kanji. Weapons you can pic up from dead enemies also count as items. So if you stealth kill an enemy by using the bow or spear you will only light a 1/2 kanji too.
Using the dog bone to kill an enemy will never count as a stealth kill, you won’t light a kanji part not get any points added to your score.
In the missions “Punish the Evil Merchant” (Rikimaru), “Execute the Evil Merchant” (Ayame), “Assassinate Nasu and Echigoya” (Tesshu) 2 bee hives can be found. By throwing items at the bee hive, the bees attack the character standing closest. If you kill someone using this method you won’t light a kanji nor get any points added to your score.

Special Move Kills
You can also use certain Special Moves such as Wrath of Heaven, Wall Kick, Feign Death … to kill your opponent with one strike. As long as your opponent is not aware of your presence (“?”-mode) while you perform the special move, his/her death will count as a stealth kill and add 20 points to your score. You can lit up to 3/4 of a kanji by using a Special Move Kill.

Find out what Special Moves you have unlocked by going to the Tenchu: Wrath of Heaven start screen and selecting “Options –> New Abilities”. All Special Moves can also be enabled and disabled by using cheat codes.